Vern Evans
On the surface, the answer to what’s the best suppressor is obvious: the quietest one. But not only is that answer untrue, it’s incomplete. Absolutely, some silencers are better than others, just like how some cars and guns are better than others, but individual considerations always come into play. If you’re looking for lazy, just buy what your friends buy and make up the reasons later. But if you want to know what goes into real testing, this one is for you.
In the lead up to our first phenomenal CANCON Carolinas, a group of us got together to give serious consideration to this question. On the panel we have RECOIL Editor-in-Chief Iain Harrison, CONCEALMENT Editor (and silencer nerd) Dave Merrill, and Gun Digest Editor Luke Hartle, and each will render a decision at the end.
The testing you see here isn’t all encompassing; we have a selection of silencers from eight manufacturers brave enough to allow potentially destructive testing. Think of this as a how-to paired with actual answers, and purchase recommendations along with the rationale. This is but the first of many silencer tests. And oh yeah — there’s some corresponding RECOILtv when you want more. Enjoy!
GUNS & GEAR
This testing is performed on hard mode — every silencer sounds great shooting subsonic .300 Blackout from a 24-inch barrel, but the same can’t be said of a shorter 5.56 shooting high-
velocity ammunition. Further, if you want testing to actually be meaningful, the variables need to be reduced. That means the same guns, ammo, and conditions across the board.
To wit, our three testers are all American Defense Manufacturing UIC MOD-2 5.56 guns with 12.5-inch barrels, topped off with EOTech EXPS sights; the only difference among them is the color of the finish. The only ammunition used was 55-grain Federal American Eagle. All tests occurred in the same environmental conditions, and acoustic testing happened away from surfaces that could warp or reflect sound.
While not every suppressor in this test has a 5.56 bore, some manufacturers opted to send .30-caliber cans even though they knew it was a 12.5-inch 5.56 test bed. Further note that the weights listed are with an attachment device. Many manufacturers like to list the weight of their cans naked, but if they can’t be screwed on the end, they aren’t really silencers anyway — at worst call it marketing, at best call it incomplete. The silencers without mounts were weighed with a lightweight direct-thread attachment.
ON DECIBELS
Decibels (dB) can be used for an awful lot of things, but for our purposes they’re a measurement of sound pressure level. There’s a lot of confusion surrounding them, and it’s not hard to mislead someone regarding this logarithmic measurement. Add into the mix that human perception of sound is different than that of a meter, and you’ll find there are general guidelines within the space of human senses, but very few hard rules.
For example: Doubling the sound pressure gives you a 6dB measurement increase, but a 10dB increase is a perceived doubling of the sound. Sound also decreases at an inverse square, so when you double the distance from the source the intensity of the sound itself is quartered.
If you’re confused, don’t worry because PhDs and audio engineers can argue about this stuff for days. You need to know OSHA states impulse noise shouldn’t exceed a peak of 140dB. This doesn’t mean you should be running around without hearing protection since your gun/can combo meters at 139dB because hearing damage is cumulative, but it is a benchmark.
You can think of decibels like altitude — the peak of the mountain, how high up it goes. Decibels aren’t concerned with matters of tone, the shape of the sound itself, or the quality of the pitch. Two different mountains may be the same height, but if one has a gentle slope to the top and another a sheer cliff that must be climbed, they aren’t the same experience. All of this to say that decibels are an important metric, but at best a decibel reading is an incomplete tale.
THE METER
You can’t just use any old decibel meter or smartphone app if you want to get good data, and you certainly can’t determine how a gun or silencer actually sounds from watching a video. The microphones and speakers used in our phones and cameras and televisions have a limited frequency range, biased toward human speech. Loud sounds compress and clip. After all, if a video camera properly recorded the entire spectrum and your speakers could reproduce it, you’d go deaf watching any sort of shooting video.
Even comparing data using different suppressors and the same flawed equipment doesn’t give you anything useful, because not only will peak noise be compressed to mush, but it takes an expensive microphone to be able to detect the sound quickly enough to discern differences.
We need an expensive, calibrated, precision instrument to properly measure decibels. In our case, a Larson Davis SoundExpert 821 with the appropriate microphones.
DECIBEL TESTING
The current sound testing standard comes from the DOD’s Design Criteria Standard Noise Limits, MIL-STD-1474E, last revised in 2015.
It should be stated that the primary concern of the DOD is how physically loud something is; how much exposure will damage your hearing. The rest of the waveform and how it subjectively feels doesn’t really matter to that bottom line.
Because of the inverse square of sound, microphone placement is essential, or all the testing is invalid. We measure decibels 1 meter left from the center of where the shock wave propagates (the muzzle of the silencer), as well as 15 centimeters to the right of the shooter’s right ear.
Before the first round is fired through a silencer, the insides are full of atmospheric gases. That same explosion that propels the projectile also ignites some of these gases, adding to the pressure and noise. We call this slightly louder shot “first round pop.” While FRP makes little difference in overall noise on a short, suppressed 5.56, we still included the FRP reading into our average.
THE LETHAL OPTOMETRIST
MIL-STD-1474E is but the latest revision in a long line of attempts at acoustic reading. The DOD published Report R-1896 on the principles of silencers and evaluation back in 1968, and while it has a ton of neat information, the details better serve historical application than the practical.
But just because input doesn’t come from a calibrated meter doesn’t mean it isn’t useful. We added a subjective test, one reportedly developed by Mitch WerBell III. Among feats and exploits like being an OSS operative, paramilitary trainer, arms dealer, and mercenary, WerBell also designed and manufactured dozens of silencers. He founded SIONICS in the 1960s and later established the [in]famous Military Armament Corporation with Gordon Ingram.
One of the ways WerBell checked the efficacy of his cans was with a test we’ve come to call the Lethal Optometrist. Secretaries would be lined up on chairs while WerBell would fire different silencers, “Which sounds better? A or B?”
Here we do the same, but instead of secretaries we used the panel as test subjects. Blindfolded in order to not bias the results, this was a single-elimination event. And though
perception of sound is subjective, both Iain Harrison and Luke Hartle chose the BOSS Guillotine, with Dave Merrill blind-picking the B&T SRBS.
Take care to note that these results DO NOT line up with what the calibrated decibel meter showed — proving once again there’s more to sound than simply how loud it is.
GAS BLOWBACK
After sound, it came time to track gas blowback. Due to deadly diseases linked to inhalation of a lot of leaded gas, the DOD has put great focus on reducing the gas that works back through the system (and exhausts in your face). Yes, there are custom adjustable/blocking gas blocks and gas tubes and bolt carriers and charging handles — but damned if it isn’t easier if you can go without.
Unfortunately, now some manufacturers just list “low backpressure” for marketing purposes, but thankfully this can actually be measured. The official method is with what’s essentially an aquarium with carbon monoxide sensors inside, but there are a few accessible ways.
The crudest way, beyond just seeing if you suck down too much during a string of fire, is by looking at the ejection patterns of spent cases. More gas in the system means higher pressure and faster bolt speeds, and with an AR-15 this equates to a more-forward shell ejection relative to unsuppressed shooting. In our experience, it works on the extreme ends of the scale, but the middle can be a toss-up; it’ll get you beyond the nose.
The more fun method is by measuring automatic rate-of-fire both unsuppressed and suppressed. More gas equals faster ROF.
FULL-AUTO FAILURES
Ever seen a silencer listed as “full auto rated?” You should know it’s probably BS unless it’s something built for a belt-fed. What it really means is if you’re in the demographic who actually owns a machine gun and uses one of their cans, they’ll warranty the result.
There’s no set standard for “full auto rated,” but surviving the vaunted SOCOM Table II firing schedule should be the start. Requiring (eight) full 30-round magazines for a total of 240 rounds, Table II prescribes rates of fire as slow as one shot per second and as fast as an automatic dump. Even silencers that can stand far more than 240 rounds straight on a machine gun sometimes break during a Table II.
At the sort of temperatures seen, you also have to worry about cook-offs, meaning ammunition goes off from heat alone as soon as it enters the chamber — no trigger pull required.
Please note that just because some silencers had issues with Table II doesn’t mean those silencers are bad or unusable, just that they aren’t the best choice for machine guns or other military applications.
BEST 5.56 SUPPRESSORS
Advanced Armament Corporation Ranger 5
- Caliber: 6mm
- Length: 5.8 inches
- Diameter: 1.5 inches
- Weight (with mount): 15 ounces
- MSRP: $900
- dB at Muzzle: 146.5
- dB at Ear: 141.9
- Gas Pressure Increase: 44%
- Table II: Pass
One of the “old school” silencer companies first founded back in the mid 1990s, AAC was one of the early silencer educators out there — it’s hard to sell things people assume are illegal, after all. Though their presence hasn’t been constant because of the company changing hands over the years, they now have the same parent as Palmetto State Armory, so we expect to see a lot more from them in the future.
If you know anything about AAC silencers, then the Ranger 5 is exactly what you expect. It’s tough as nails, and one of the few on this list advertised as “full auto rated” we actually outright believed.
| Advanced Armament Corp. | $900 |
Aero Precision Lahar-30
- Caliber: .30
- Length: 5.9 inches
- Diameter: 1.58 inches
- Weight (with mount): 15.9 ounces
- MSRP: $893
- dB at Muzzle: 141.9
- dB at Ear: 145.9
- Gas Pressure Increase: 52%
- Table II: Pass
We often find .30-caliber cans to do worse in sound testing, but here the Aero Precision Lahar-30 took home top marks at the muzzle decibel meter at 141.9dB but was higher at the ear. It also had the highest ROF increase among our test group at 52 percent.
With an Inconel blast baffle and 17-4 stainless steel construction, the tubeless
Lahar-30 shrugged off the Table II and asked for more.
All told, we found Aero Precision silencers to be right where Aero Precision rifles are —respectable and higher than the middle. Very versatile, affordable silencer.
| Silencer Central | $700 |  |
Brügger & Thomet Print-X SRBS-Ti (Leathal Optometrist Winner & Dave Merrill Editor’s Choice)
- Caliber: 5.56mm
- Length: 7.4 inches
- Diameter: 1.73 inches
- Weight (with mount): 11.3
- MSRP: $950
- dB at Muzzle: 142.2
- dB at Ear: 138.9
- Gas Increase: 23%
- Table II: Pass
There was a time when any titanium silencer would’ve been shrugged off or laughed off when it came to serious use, because when subjected to high heat and pressures it starts to send off white sparks. The B&T Print-X SRBS-Ti had a few sparks, but far fewer than we were used to.
3D printed with direct metal laser sintering (DMLS), this B&T silencer was the lightest of our bunch despite being more than 7 inches long paired with a fatter 1.73-inch diameter. Plus, the gray suppressor changed colors in a pleasing way after finishing the Table II test.
In addition to being the lightest silencer, the SRBS-Ti had the smallest ROF increase at 23 percent, which is no surprise if you know anything about their low-pressure efforts.
“The sound profile and engineering coalesce in a way that’s hard to describe, but I like it all.” -Dave Merrill
| Silencer Central | $1,350 | |
BOSS Silencers Guillotine (Leathal Optometrist Winner & Luke Hartle Editor’s Choice)
- Caliber: 5.56mm
- Length: 6 inches
- Diameter: 1.5 inches
- Weight (with mount): 12.1 ounces
- MSRP: $500
- dB at Muzzle: 144.0
- dB at Ear: 138.7
- Gas Increase: Unknown but high
- Table II: Fail
We don’t have ROF increases for the BOSS Guillotine because it suffered a catastrophic failure when shooting the SOCOM Table II, but we know it would’ve been high. When Luke Hartle was shooting velocity data, he wasn’t pleased with the sheer amount of gas in his face. And yet, this was still his overall choice.
“The BOSS Guillotine 5.56 stood out and truly impressed me. It’s small, it’s inexpensive at about $500, and I chose its sound profile as most appealing over all the others — while blindfolded! The fact that it failed the Table II test is a moot point for me; I’ll never use a can like that in real application.” -Luke Hartle
| B.O.S.S. Silencers | $500 | |
KG Made R556A2 (Iain Harrison Editor’s Choice)
- Caliber: 5.56
- Length: 6.4 inches
- Diameter: 1.6 inches
- Weight (with mount): 22.1 ounces
- MSRP: $975
- dB at Muzzle: 145.7
- dB at Ear: 146.1
- Gas Increase: 37%
- Table II: Pass
There’s no way around it, this suppressor is absolutely aesthetically pleasing. You just know it’s meant for an apocalypse-level of abuse by looking at it. Though it’s the heaviest of the bunch, there was great confidence it would perform well with the Table II, and it most certainly did.
Regarding gas blowback, it was in the lower half, and the muzzle device attachment method is quick and painless.
“This wouldn’t be my first pick for a hunting rifle. In fact, it wouldn’t be my 30th, but if you’re looking for one can that’ll stand up to whatever abuse you can throw at it, the KGM is money. As Dave Merrill is fond of opining, there’s a lot of BS thrown around when it comes to cans being “full auto rated,” and you will always find someone on the internet with an opinion that suppressor X from company Y will stand up to use on a machine gun. Usually, that someone doesn’t have a machine gun. I do, and this is the suppressor I’d run on it.” -Iain Harrison
| Silencer Central | $975 | |
LMT Advanced Technologies ATIONLT Ion LT
- Caliber: .30
- Length: 8.14 inches
- Diameter: 1.74 inches
- Weight (with mount): 18 ounces
- MSRP: $1,300
- dB at Muzzle: 148.2
- dB at Ear: 139.5
- Gas Increase: 28%
- Table II: Pass
LMT stands for Lewis Machine & Tool, first founded back in 1980 with government contracts in mind — and they got them, just mostly overseas in the southern hemisphere these days. The joke is that they essentially do not have a marketing department, largely because they don’t need it; if you know, you know.
LMT released some of their early consumer silencers at CANCON, so it was absolutely appropriate they participated in our first bout of testing. Everything they make is designed to be bomb-proof, and at the factory they perform their own Table II testing. Needless to say, performance was admirable. Also, noteworthy it had the second-best ROF increase in our testing.
| Silencer Central | $1,250 | |
Troy Industries TPRS Kryptos
- Caliber: 5.56mm
- Length: 6.5 inches
- Diameter: 1.65 inches
- Weight (with mount): 21.4 ounces
- MSRP: $1,200
- dB at Muzzle: 144.4
- dB at Ear: 138.1
- Gas Increase: 51%
- Table II: Pass
Multiple people commented on how good this silencer looks mounted on the end of a rifle.
The Kryptos comes complete with a specific muzzle device with open tines on the end. Even tucked inside, this device can emit a high-pitched ringing sound after firing, which may be annoying/distracting. Though the Troy Kryptos made it through the Table II, it began occasionally cooking off rounds during the last few magazines.
A stand-out feature of the Troy Kryptos is that it’s a reflexive silencer. That means part of the silencer goes back over the barrel, adding to internal volume without additional length. This extra volume behind the blast isn’t as efficient as it is in front of the muzzle, but it still helps. It also gives the rifle a shorter profile; even though the Kryptos is 6.5 inches long, it only adds 4 inches to the system.
| Troy Industries | $1,200 | |
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